TY - JOUR
T1 - Performance of a high-pressure xenon ionization chamber for environmental radiation monitoring
AU - Kim, H. S.
AU - Park, S. H.
AU - Ha, J. H.
AU - Kim, Y. K.
AU - Kim, J. K.
AU - Cho, S. Y.
PY - 2008/2
Y1 - 2008/2
N2 - High-pressure xenon (HPXe) ionization chambers are ideal for use in uncontrolled environments, as a detector's response has been shown to be uniform over large temperature ranges (20 - 170 {ring operator} C). A cylindrical HPXe ionization chamber, which was configured with a shielding mesh to improve its energy resolution, was designed on the basis of an EGSnrc simulation code to extract an optimal density of Xe gas and a thickness of the chamber's wall. A Garfield, which was coupled with a Maxwell electric field calculator, was also employed for the electron drift simulations due to the geometry of the adapted shielding mesh. Shielding inefficiency was also calculated. A spherical ionization chamber was also designed to monitor an environmental radiation level and the responses for low dose rates with the fabricated HPXe ionization chamber were compared. A noble gas system was constructed to create a noble gas with a high purity and to inject the noble gas at up to 60 atm. The combination of an oxisorb, a molecular sieve, and a high-temperature getter can minimize the electro-negative impurities, such as the O2 and N2 gas, to below about several ppb levels. Preliminary tests such as leakage currents, saturation currents, and gas leak tests were performed. The performance of the two fabricated ionization chambers at a low dose rate was tested by using a conventional shadow technique with a NIST certified 0.906 mCi 226Ra standard source in a calibration room at KAERI.
AB - High-pressure xenon (HPXe) ionization chambers are ideal for use in uncontrolled environments, as a detector's response has been shown to be uniform over large temperature ranges (20 - 170 {ring operator} C). A cylindrical HPXe ionization chamber, which was configured with a shielding mesh to improve its energy resolution, was designed on the basis of an EGSnrc simulation code to extract an optimal density of Xe gas and a thickness of the chamber's wall. A Garfield, which was coupled with a Maxwell electric field calculator, was also employed for the electron drift simulations due to the geometry of the adapted shielding mesh. Shielding inefficiency was also calculated. A spherical ionization chamber was also designed to monitor an environmental radiation level and the responses for low dose rates with the fabricated HPXe ionization chamber were compared. A noble gas system was constructed to create a noble gas with a high purity and to inject the noble gas at up to 60 atm. The combination of an oxisorb, a molecular sieve, and a high-temperature getter can minimize the electro-negative impurities, such as the O2 and N2 gas, to below about several ppb levels. Preliminary tests such as leakage currents, saturation currents, and gas leak tests were performed. The performance of the two fabricated ionization chambers at a low dose rate was tested by using a conventional shadow technique with a NIST certified 0.906 mCi 226Ra standard source in a calibration room at KAERI.
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U2 - 10.1016/j.radmeas.2007.12.040
DO - 10.1016/j.radmeas.2007.12.040
M3 - Article
AN - SCOPUS:45149106171
VL - 43
SP - 659
EP - 663
JO - Radiation Measurements
JF - Radiation Measurements
SN - 1350-4487
IS - 2-6
ER -